A microenvironmental sensor may be in the form of a probe carrying a single sensing interface or an array of such interfaces, each interface being of micro dimensions and mounted on a substrate of the probe, the substrate having micro transverse dimensions. Typically the interface is carried on a shank portion of the probe. Such a probe is used in conjunction with signal processing circuitry.
A typical application of microenvironmental sensors is in physiological work in which it is frequently necessary to use biosensors of extremely small physical dimensions. For example, it may be desired to sense neurological changes of electrical potential by implanting a sensing interface in a single nerve cell with minimal damage to and effect on the surrounding tissue and environment.
Conventional microenvironmental sensors are large, they have substrates of more than 100.mu. wide, 25-30.mu. thick and sensing interfaces of dimensions more than about 10.mu.. These suffer from the disadvantages of disturbing and often irreversibly modifying the microenvironment into which they are placed, especially of the microenvironment around the sensing interfaces.